Objective: Several studies have reported increasing number of therapeutic failures with antiretroviral drugs in HIV infected patients. The emergence of viral resistant strains is a major problem for the medical management of infected individuals. In this study we aimed to determine the prevalence of secondary antiretroviral resistance-associated mutations in Iranian HIV infected patients.

Methods: A total of 40 HIV infected patients under antiretroviral drug treatment were enrolled in this study. All of the patients were received antiretroviral treatment for at least 1 year. One protease inhibitor (PI) or one nonnucleoside transcriptase inhibitor (NNRTI) in combination with 2 nucleoside transcriptase inhibitors (NRTI) are considered for antiretroviral therapy.

The HIV pol region including viral protease and reverse transcriptase genes were amplified and sequenced for determining genotype, subtype and antiretroviral resistance-associated mutations.

Results: Sequencing of the samples revealed that 40% of strains belonged to subtype B, 20% subtype A, 35% were A/D and 5% were CRF01-AE recombinants. Drug resistance-associated mutations identified more common in subtype A/D recombinant. Virus samples from 30% of participants showing no drug resistance mutation and 70% of them carried 2 drug resistance mutations. Dual-class drug-resistant virus (NRTI and NNRTI) was present in 22% of participants, and 43% had virus with triple-class drug resistance.

The prevalence of NRTI mutations was 77% with M184V and V118I present in 55% and 48% of samples respectively. The prevalence of NNRTI mutations was 66% which P225H mutations were present in 30% of study specimens. The prevalence of PIs mutations was 44%. Major PIs mutation L90M was seen in 45% and minor protease inhibitor mutation A71V was detected in 50% of samples. The other major PIs mutations were V32I, L33F, M46I, I54V, V86T, and I84V.

The highest frequency of resistance to PIs was related to nelfinavir (60%, high level resistance) and saquinavir (60%, intermediate resistance).

For NNRTI, the frequencies of resistant isolates were 56% to nevirapine, 44% to delavirdine and 44% to efavirenz, and for NRTI was 56%, high level resistance to lamivudine.

Conclusions: Our study showed a high prevalence of secondary resistance mutations in Iranian HIV infected patients. Continued surveillance of resistance patterns is warranted to guide therapeutic approaches as selection of second-line regimens in Iran.

Session Details

Date:

10/04/2010

Time:

00:00-00:00

Session name:

Abstracts 20th European Congress of Clinical Microbiology and Infectious Diseases